diff --git a/guides/source/security.textile b/guides/source/security.textile
index ac64b82bf6..ac55d60368 100644
--- a/guides/source/security.textile
+++ b/guides/source/security.textile
@@ -627,7 +627,7 @@ h4. Whitelists versus Blacklists
 
 -- _When sanitizing, protecting or verifying something, whitelists over blacklists._
 
-A blacklist can be a list of bad e-mail addresses, non-public actions or bad HTML tags. This is opposed to a whitelist which lists the good e-mail addresses, public actions, good HTML tags and so on. Although, sometimes it is not possible to create a whitelist (in a SPAM filter, for example), _(highlight)prefer to use whitelist approaches_:
+A blacklist can be a list of bad e-mail addresses, non-public actions or bad HTML tags. This is opposed to a whitelist which lists the good e-mail addresses, public actions, good HTML tags and so on. Although sometimes it is not possible to create a whitelist (in a SPAM filter, for example), _(highlight)prefer to use whitelist approaches_:
 
 * Use before_filter :only => [...] instead of :except => [...]. This way you don't forget to turn it off for newly added actions.
 * Use attr_accessible instead of attr_protected. See the mass-assignment section for details